Three-position relay



R. M Gi'L's'0N..- THREE-POSITION RELAY.- APPLIC' ATION F|LE D JUNE 26, 1919.

Patented May 23 1922.

, INVENTOR.

, F17'- 2 I HQ; ATTORNEY.

UNITED STATES PATENT OFFICE.

ROBERT M. GInsoN, or rrr'rsnnneir, PENNSYLVANIA, ASSIGNOR'TO THE UNION SWITCH & SIGNAL COMPANY, or SWISSVALE, PENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIA.

I THREE-POSITION RELAY.

Specification of Letters Patent.

Patented May-2e, 1922.

Application filed June 26, 1919.- Serial No. 306 807.

To all whom may concern:

Be it known that I, Ronnnr MJGrnson, a. citizen of the United States, residing at Pittsburgh, in the county of Allegheny and State of Tennsylvani'a, have invented certain new and useful Improvements in Three-Pd. sition Relays, of which the following is a, specification. Y Y

My invention relates to three-position electrical relays, and particularly to relays of this type comprising a contact operating member movable in opposite directions from an intermediate position to two extreme positions.

I will describe one form of relay embodying my invention, and will then point out thenovel features thereof in claims.

In the accompanying drawings, Fig, 1 isa view showing in side elevation the-operating parts of one form of relay embodying my invention; Fig. 2 is a top view of part of the relay shown in Fig. 1, and illustrating particularly the means for moving the contact operating member of the relay.

Similar reference characters refer to similarparts in each of the views.

Referrin first to Fig. 1, the reference character designates a base plate which supports all of the other parts of the relay.

Pivotally mounted at the point 2 is avane V of non-magnetic, electro-conductive material such aluminum, which vane constitutes the movable contact-operating member of the relay. The vane V is biased to an intermediate position, thisbeing the position in which it is shown in the drawing but it may be moved in the direction indicated by the arrow (.4 to an upper BXlJlUlHG position,

and in the direction indicated by the arrow 2'; to a lower extreme position, these movements being accomplished by means hereinafter explained.

The vane V is biased by its own weight to move from its upper extreme position to its The biasing force.

lower extreme position. tending to swing the vane from its lower extreme position to the intermediate position is produced by a counterweight comprising a rod 3'pivotally mounted at 3 and carrying a weight WV. this counterweight is limited by a screw 7 which passes through the weight WV and'rests on the base plate B. Thecounterweight is connected with the vane by a link 4; the up- The downward movement of per end of which is pivotally connected to a The lower endcrank 5 attached to the vane. of the link t is provided with a slot 4 through which passes a pin 6 carried by the counterweight rod 8. The parts are so adjusted that when the vane V is in its intermediate position and screw 7 is resting on thebase' plate, the pin 6 isat the lower end of the slot 4P. It follows, then, that if the vane is moved from its'intermediateposition in the direction of arrow 7), weight W is raised; and that when the force thus acting on the vane is removed the vane will be re turned to its intermediate position. The vane isfree to swing upwardly from its intermediate position without interference by the counterweight because of the slot 4 in link l.

. In order to provide'for adjustment of the torque exerted on the vane by the counter weight, the rod 8 is preferably extended to the left of the pivotal point 3 and threaded to receive nuts 8.

The contact apparatus controlledby the vane. V comprises a rocker 10 pivotally mounted at 10 and provided with an open ating arm 13 which is connected with the crank 5 by a link 9.-The rocker 10 carries two contact members 11 and 12 which engage with two fixed contact members 11 and 19% respectively. The parts are so adjusted that when the vane occupies its in tern'iediate position, both contacts l111'- and 12---l2 are open; that when the vane' 2), and a third core 15 of similar material arranged with its pole-pieces on opposite sides of the vane and between the pole-pieces of the cores 11 and let. The cores 14 and 14: are provided with coils L and L which are usually"connected in series, and core 15 is provided with a coil T. If the three coils are supplied with alternating currents, it

termedi ate position to two extreme positions, and biased by its own Weight to move from one extreme position to the other extreme position, counterwcighting means for returning said member from the said other extreme position to said intermediate position, the Weight of said member being depended upon to return the member from the first-mentioned extreme position to the intermediate position, means for moving said member from its intermediate position to said extreme positions in opposition to the biasing forces acting on the member a contact closed by said member when the latter occupies one extreme position, and a second contact closed by said member when the latter occupies the other extreme position.

In testimony whereof I afiix my signature in presence of tWo Witnesses.

ROBERT M. G'ILSON.

Witnesses:

A. HERMAN WEGNER, R. L. KISTLER. 

